MIUI 8 Global Stable ROM V8.2.3.0.MHOMIDLupdate for Redmi Note 3 is released. So, it's a time for your system to get updated. If you are using recent MIUI 8 Global Stable ROM, then you will be receiving the OTA update via Updater App. If you cannot wait then you can download the ROM packages from the link given below and get updated.

For flashing the Fastboot ROM you need to download the MiFlash tool. You can download the flash tool from Here

Also you need to unlock your device if you are flashing the Fastboot ROM

Please go to "Updater" and choose full package zip file to upgrade. If you are updating from other ROMs, please don't forget to back up and wipe all data before flashing to avoid data conflicts. Use Clean All option in the new Mi Flash Beta Tool while flashing to perform a full wipe and fresh install.